
interface Lockable 
{
	public void setKey(int k);
	public void lock(int k);
	public void unlock(int k);
	public Boolean locked();
	
}

class Account implements Lockable
{
	
	private int id;
	private String name;
	private float money;
	
	public void napTien(float a)
	{
		if(locked() == false) 
		{
			money += a;
		}				
	}
	
	public void rutTien(float a)
	{
		if(locked() == false)
		{
			money -= a;
		}
	}
	
	public void chuyenKhoan(Account b, float a)
	{
		if(locked() == false)
		{
			b.money += a;
			money -= a;
		}
	}
	
	@Override
	public void setKey(int k) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void lock(int k) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void unlock(int k) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public Boolean locked() {
		// TODO Auto-generated method stub
		return null;
	}
	
}